Prepare for Flux v2.4.0

[stefanprodan]

Flux 2.4.0 promotes the Bucket API to GA and comes with new features, bug fixes and performance improvements.

📅 Target dates: 30 September

🚀 Roadmap milestone: https://fluxcd.io/roadmap/#v24-q3-2024

Highlights

• Proxy support for container registries (OCIRepository, ImageRepository) and S3-compatible storage (Bucket)
• STS support for AWS and LDAP (Bucket)
• Teams notifications using the Microsoft Adaptive Card API (Alert Provider)
• Azure DevOps auth using OIDC and AKS Workload Identity (GitRepository, ImageUpdateAutomation)
• Adopt exiting in-cluster resources when reconciling releases (HelmRelease)

API promotion

• Bucket source.toolkit.fluxcd.io/v1 (v1beta2 deprecated)

Dependencies updates

• Kubernetes 1.31
• Go 1.23
• Helm 3.16
• SOPS 3.9
• Cosign 2.4
• Notation 1.2

Release checklist

• source-controller v1.4.1
• kustomize-controller v1.4.0
• notification-controller v1.4.0
• helm-controller: v1.1.0
• image-reflector-controller v0.33.0
• image-automation-controller v0.39.0
• flux-benchmark v2.4.0
• flux2 v2.4.0
• terraform-provider-flux v1.4.0

Documentation

• Update docs to promoted APIs
• Publish Flux release change log to GitHub & Slack
• Publish v2.4 website

Conformance testing

Distribution	Versions
Kubernetes KinD	1.29.7, 1.30.2, 1.31.1
OpenShift	4.15.0-okd
K3s	1.29.9, 1.30.5, 1.31.1
Google Cloud	1.29.7-gke.1104000

TODO

• Update Flux components to Kubernetes 1.31 #4928
• Build Flux components with Go 1.23 #4927
• Allow specifying a custom CA certificate in Bucket API source-controller#973
• Allow specifying HTTP/S proxy in Bucket API  source-controller#1493
• Full proxy support in Bucket source source-controller#1563
• Add support for custom AWS STS endpoint for bucket/S3 source source-controller#1423
• Add support for LDAP STS endpoint for Bucket generic provider source-controller#1564
• Allow specifying HTTP/S proxy in OCIRepository API source-controller#1492
• Fix Helm index validation for Artifactory source-controller#1516
• Fix HelmChart local dependency resolution for name-based path source-controller#1539
• Promote Bucket API to v1 source-controller#1592
• Update notaryproject/notation-go to 1.2.1 source-controller#1603
• [RFC-0007] Enable Azure OIDC for Azure DevOps repositories source-controller#1591
• [RFC-0007] Enable Azure OIDC for Azure DevOps Repository image-automation-controller#747
• Add proxy support for ImageRepository API image-reflector-controller#627
• Allow cross-shard dependency check kustomize-controller#1248
• Allow cross-shard dependency check helm-controller#1070
• Ignore 'v' version prefix in OCI artifact and Helm chart helm-controller#990
• Re-enable logging json patch on StatusDrifted helm-controller#1010
• Allow overwriting inline values with targetPath helm-controller#1060
• Update Helm to v3.16.1 and enable the adoption of existing resources helm-controller#1062
• Add disableSchemaValidation to Helm install/upgrade actions helm-controller#1068
• Update SOPS to v3.9.0 kustomize-controller#1212
• New flag to disable detailed metrics for path notification-controller#841
• telegram notifier should escape with metadata key notification-controller#829
• Add MS Adaptive Card payload to msteams Provider notification-controller#920
• Add proxy support for oci/auth login pkg#808
• Implement new packages auth, azure and git for passwordless authentication scenarios pkg#789
• Add new integration tests for Azure OIDC for git repositories pkg#793
• flux bootstrap github fails for repositories with custom properties #4958
• Add part-of label to controllers base #4842
• Introduce visibility flag for bootstrap gitlab #4866
• Fix GitHub bootstrap for repositories with custom properties  #4959
• Recursively diff Kustomizations #4939
• [RFC-0007] Add --provider flag to flux create source git #4986
• Add flux create secret proxy command #5010
• Remove TLS deprecated flags from flux create secret #5011
• Add winget to CLI windows installation instructions website#2049